Astwood Bank appears as a regional daily highest temperature performer with almost monotonous regularity. With equal regularity it also records noticeably higher than even its near neighbouring private/amateur weather stations which is surprising considering Astwood Bank is just the same sort of amateur back garden site as its neighbours.
52.24808 -1.93503 Met Office CIMO Assessed Class 5 installed 1/1/1976
Before going any further with this boringly regular daily record setter, a reminder of its CIMO Class 5 status. Firstly “Site not meeting the requirements of class 4.” This indicates this site meets no internationally recognised regulatory defined standard whatsoever – any Stevenson screen in an area expressly designed area to create an artificially temperature elevated micro climate could meet this lack of any standard – which of course many do e.g. Kingston Maurward.
Secondly “Class 5 (additional estimated uncertainty added by siting up to 5 °C)” So in reality its readings should never be accepted as likely to be genuinely accurate with such a massive error margin.
So to examine the detail of this acknowledged totally unregulated and wildly inaccurate site, Astwood Bank lies within a back garden with no enclosure whatsoever to eliminate external factors, in front of a hedge alongside flower beds, shrubs and all the comings and goings of domestic life. In the absence of any Streetview or close up, this is what 2D aerial imagery provides.
This site is no more likely to provide accurate readings than literally millions of other back garden sites nationwide, will be highly susceptible to aitken effect low wind velocity temperature distortion and the Met Office obviously knows all this so what makes this back garden so preferred? The screen was initially installed in 1976 presumably as an amateur set up subsequently adopted by the Met Office. Following 34 years of reliable reading observations the site was automated in 2010. Whilst diligent record taking is commendable, it can in no way make up for an unsatisfactory setting. Exactly what the motivation was for the Met Office to upgrade is not known. What is evident is that so many of the adopted and upgraded sites like Astwood Bank, Hull East Park, Cavendish, Chillingham Barns and others are all very poor Class 5 sites AND go on to become regular star performers in the daily extremes stakes.
I will leave it at that point regarding possible Met Office motives but simply emphasize that sites like Astwood Bank raise lots of questions regarding the reasons for their inclusion in the historic climate record that should be answered.
via Tallbloke’s Talkshop
June 21, 2025 at 02:48PM
Iowa Climate Science Education 